A flash-spun sheet material with better single peeling degree and its application

Abstract

The present invention relates to a flash-spun sheet material with an excellent single peelability and its application. The flash-spun sheet material comprises polyethylene, has a thickness of 0.11 to 0.29 mm, and a single peelability of 10 to 26 (N·s / mm). Single peelability is calculated as (logarithmic peel strength * Gurley air resistance) / thickness. The flash-spun sheet material has a greater CD peel strength than the MD peel strength. The sheet material of the present application has an excellent single peelability and is therefore suitable for a wide range of applications.

Description

Technical Field

[0001] The invention relates to the technical field of flash spinning production, in particular to a flash spinning sheet material with better single peeling degree and application thereof. Background Art

[0002] The peel strength of flash-steamed non-woven fabrics is mainly related to the following factors: (1) Fiber raw materials: The type, length, fineness and strength of the fibers used will significantly affect the peel strength of the non-woven fabric. For example, fibers with high strength and long length usually make the non-woven fabric have better peeling performance. (2) The bonding method between fibers: Common bonding methods include thermal bonding, chemical bonding and needle punching. Different bonding methods and the degree of bonding will directly affect the peel strength of the non-woven fabric. Factors such as thermal bonding temperature, type and amount of chemical adhesives may have an effect on it. (3) Finishing process: For example, the peel strength of non-woven fabrics that have been finished by coating, waterproofing, etc. may change. (4) Storage and use environment: Environmental conditions such as humidity and temperature may affect the performance of non-woven fabrics and thus change their peel strength. For flash-steamed materials, especially those used as medical packaging materials, if the peel strength is too low, it is easy to be damaged, which may cause contamination or even damage to medical devices. Therefore, in response to this technical problem, we improved the raw materials and process of flash spinning to solve this technical pain point.

[0003] Chinese patent number CN114763634 relates to a flash-spun sheet material, wherein the tear index loss value ΔX of the sheet material is 0.15 to 0.35; ΔX = 1-X2 / X1; X1 is the tear index of the unaged sheet material; X2 is the tear index of the aged sheet material; the aging process conditions are: irradiance in the wavelength range of 300 to 400 nanometers is 60 ± 2 w / m 2 , the black mark temperature is 65±2°C, the air temperature of the test chamber is 38±3°C, the relative humidity is 50±10%, and the drying time is 720 hours. The sheet material of the present application has good antioxidant function.

[0004] Chinese patent number CN114908478B relates to a light and thin flash-evaporated polymer nonwoven fabric with a wet tensile strength retention rate of 0.70-0.85, a front smoothness of 180-250 seconds, and a grammage of 35-45 g / m 2 ; The present invention is prepared by a flash evaporation process, and the raw material is polyethylene; the thin and light flash-evaporated polymer non-woven fabric of the present application has good toughness and softness, and at the same time has a good wet tensile strength retention rate, which is beneficial to prolonging its service life.

[0005] Chinese Patent No. CN116949681 relates to a flash-spun, yellowing-resistant sheet and its manufacturing method. The sheet's raw materials include a polymer and a modifier, the modifier being a composite of an antioxidant and a brightener, the antioxidant being tetrakis(2,4-di-tert-butylphenol)-4,4'-biphenyl diphosphite, and the brightener being barium sulfate. Yellowing resistance of the sample is determined using the CIEL*, a*, b* (CIE, 1976) color system. The sheet exhibits an L* value of 70 or greater, an a* value of -2.5 to -0.5, and a b* value of -6.0 to -2.5. This application overcomes the technical problem of sheet yellowing by improving the raw materials.

[0006] Chinese patent number CN116590846 relates to a flash-spun polyethylene film material with good toughness and its manufacturing method, wherein the raw material comprises polyethylene, and the gram weight G of the flash-spun polyethylene film material is greater than 50g / m 2 The initial toughness Z0 of the polyethylene film material is 20 to 35 (N·m) / g; Z0 = [RM × EM + RT × ET] / G; where RM is the tensile strength in the MD direction; RT is the tensile strength in the TD direction; EM is the tensile elongation in the MD direction; and ET is the tensile elongation in the TD direction. The flash-spun polyethylene film material is exposed to a dry heat atmosphere at 90°C for 6 hours, then cooled at 25°C and 65% relative humidity for 24 hours. Its light transmittance is then measured to be 8% to 13%. Light transmittance is measured according to GBT 2410-2008, and is the ratio of the luminous flux transmitted through the sample to the luminous flux incident on the sample, expressed as a percentage. Due to its excellent toughness, this application has broad application prospects in fields such as packaging agriculture.

[0007] Currently, the above literature has described some properties of flash products, but no description of single stripping degree is found. Summary of the Invention

[0008] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a flash-spun sheet material with better single peeling degree and its application.

[0009] The object of the present invention is achieved through the following technical solutions:

[0010] A flash-spun sheet material with a better single peeling degree, characterized in that the raw material of the flash-spun sheet material comprises polyethylene, and the thickness of the flash-spun sheet material is 0.11 to 0.29 mm;

[0011] The single peeling strength of flash-spun sheet materials is 10 to 110 (N•s / mm);

[0012] Single peel strength = (logarithmic peel strength * Gurley air resistance) / thickness;

[0013]

[0014] The test standard for peel strength is the peel strength test method for adhesive interlining garments FZ / T 80007.1-2006;

[0015] The test standard for Gurley air resistance is GB / T 458-2008, which states that paper and board—Determination of air permeability. Gurley air resistance is measured in seconds, using the time it takes for 100 ml of gas to pass through.

[0016] The unit of logarithmic peel strength is N; the unit of Gurley air resistance is second, and the unit of thickness is millimeter.

[0017] The peeling strength of the flash-spun sheet material in the CD direction is greater than that in the MD direction;

[0018] The CD peeling strength of the flash spun sheet material is greater than 0.4N.

[0019] The CD peeling strength of the flash spun sheet material is greater than 0.5N.

[0020] The CD peeling strength of the flash spun sheet material is greater than 0.6N.

[0021] The CD peeling strength of the flash spun sheet material is greater than 0.7N.

[0022] The CD peeling strength of the flash spun sheet material is greater than 0.8N.

[0023] The single peeling strength of the flash-spun sheet material is 10 to 20 (N•s / mm).

[0024] The single peeling strength of the flash-spun sheet material is 20 to 30 (N•s / mm).

[0025] The single peeling strength of the flash-spun sheet material is 30 to 40 (N•s / mm).

[0026] The single peeling strength of the flash-spun sheet material is 40 to 50 (N•s / mm).

[0027] The single peeling strength of the flash-spun sheet material is 50 to 60 (N•s / mm).

[0028] The single peeling strength of the flash-spun sheet material is 60 to 70 (N•s / mm).

[0029] The single peeling strength of the flash-spun sheet material is 70 to 80 (N•s / mm).

[0030] The single peeling strength of the flash-spun sheet material is 80 to 90 (N•s / mm).

[0031] The single peeling force of the flash-spun sheet material is 90 to 100 (N•s / mm).

[0032] The thickness of the flash-spun sheet material is 0.15 to 0.20 mm.

[0033] The thickness of the flash-spun sheet material is 0.16 to 0.18 mm.

[0034] The invention discloses a flash-spun sheet material with better single peeling degree and its application in the textile field or medical packaging.

[0035] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0036] (1) melting nano-attapulgite, hexagonal boron nitride and polyethylene particles to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 1-2%, the mass fraction of the hexagonal boron nitride is 0.5-1%, and the balance is polyethylene particles.

[0037] Hexagonal boron nitride has a unique crystal structure, in which B atoms and N atoms are connected by strong covalent bonds, forming a layered structure. This structure creates polar interactions between hexagonal boron nitride layers that are stronger than the van der Waals forces between graphite layers. This creates effective physical crosslinks in the flash-spun sheet material, enhancing the peeling strength between the flash-spun fibers.

[0038] Nano-attapulgite has an elongated fibrous morphology that interweaves and overlaps within the flash-spun polyethylene sheet material, forming a continuous network. The nano-attapulgite fills the gaps between the flash-spun polyethylene fibers, increasing the density of the flash-spun sheet material. At the same time, its inherent high strength and high modulus properties can transfer stress and enhance the overall strength of the flash-spun sheet material. When microcracks form in the flash-spun sheet material due to external forces, the nano-attapulgite network structure hinders further expansion of the cracks, and its fibers bridge the cracks, absorbing and dispersing energy, thereby increasing the peel strength of the flash-spun polyethylene non-woven fabric.

[0039] (2) pressurizing the spinning solvent to 6-9 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 7-16%, and the remainder is the spinning solvent;

[0040] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0041] Compared with the prior art, the present invention has the following positive effects:

[0042] The distribution and interaction of hexagonal boron nitride and nano-attapulgite in the raw materials of this application in the flash-spun sheet material can also more effectively disperse stress when the flash-spun sheet material is subjected to stress, form more effective physical cross-linking, reduce the formation and expansion of cracks, and improve the peel strength of the flash-spun sheet material. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 SEM image of Example 2 of the present application. DETAILED DESCRIPTION

[0044] The following provides a specific embodiment of a flash-spun sheet material with a better single peeling degree and its application according to the present invention.

[0045] Example 1

[0046] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0047] (1) Nano-attapulgite, hexagonal boron nitride and polyethylene particles are melted to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 1%, the mass fraction of the hexagonal boron nitride is 0.5%, and the balance is the polyethylene particles.

[0048] Hexagonal boron nitride has a unique crystal structure, in which B atoms and N atoms are connected by strong covalent bonds, forming a layered structure. This structure creates polar interactions between hexagonal boron nitride layers that are stronger than the van der Waals forces between graphite layers. This creates effective physical crosslinks in the flash-spun sheet material, enhancing the peeling strength between the flash-spun fibers.

[0049] Nano-attapulgite has an elongated fibrous morphology that interweaves and overlaps within the flash-spun polyethylene sheet material, forming a continuous network. The nano-attapulgite fills the gaps between the flash-spun polyethylene fibers, increasing the density of the flash-spun sheet material. At the same time, its inherent high strength and high modulus properties can transfer stress and enhance the overall strength of the flash-spun sheet material. When microcracks form in the flash-spun sheet material due to external forces, the nano-attapulgite network structure hinders further expansion of the cracks, and its fibers bridge the cracks, absorbing and dispersing energy, thereby increasing the peel strength of the flash-spun polyethylene non-woven fabric.

[0050] (2) pressurizing the spinning solvent to 6.5 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 9%, and the remainder is the spinning solvent;

[0051] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0052] The flash-spun sheet material in this embodiment can be used in the textile field or medical packaging.

[0053] Example 2

[0054] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0055] (1) Nano-attapulgite, hexagonal boron nitride, and polyethylene particles are melted to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 1.5%, the mass fraction of the hexagonal boron nitride is 0.75%, and the balance is the polyethylene particles.

[0056] (2) pressurizing the spinning solvent to 8 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 10%, and the remainder is the spinning solvent;

[0057] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material. Figure 1 This is the SEM image of the flash-spun sheet material.

[0058] The flash-spun sheet material in this embodiment can be used in the textile field or medical packaging.

[0059] Example 3

[0060] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0061] (1) Nano-attapulgite, hexagonal boron nitride and polyethylene particles are melted to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 2%, the mass fraction of the hexagonal boron nitride is 1%, and the balance is the polyethylene particles.

[0062] (2) pressurizing the spinning solvent to 9 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 11%, and the remainder is the spinning solvent;

[0063] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0064] The flash-spun sheet material in this embodiment can be used in the textile field or medical packaging.

[0065] Comparative Example 1

[0066] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0067] (1) Nano-attapulgite, hexagonal boron nitride and polyethylene particles are melted to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 0.5%, the mass fraction of the hexagonal boron nitride is 0.25%, and the balance is the polyethylene particles.

[0068] (2) pressurizing the spinning solvent to 8 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 10%, and the remainder is the spinning solvent;

[0069] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0070] The flash-spun sheet material in this comparative example can be used in the textile field or medical packaging.

[0071] Comparative Example 2

[0072] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0073] (1) melting hexagonal boron nitride and polyethylene particles to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of hexagonal boron nitride is 0.75%, and the balance is polyethylene particles.

[0074] (2) pressurizing the spinning solvent to 8 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 10%, and the remainder is the spinning solvent;

[0075] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0076] The flash-spun sheet material in this comparative example can be used in the textile field or medical packaging.

[0077] Comparative Example 3

[0078] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0079] (1) melting nano-attapulgite and polyethylene particles to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 1.5%, and the balance is the polyethylene particles.

[0080] (2) pressurizing the spinning solvent to 8 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 10%, and the remainder is the spinning solvent;

[0081] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0082] The flash-spun sheet material in this comparative example can be used in the textile field or medical packaging.

[0083] Comparative Example 4

[0084] A method for processing a flash-spun sheet material with a better single peeling degree comprises the following technical steps:

[0085] (1) Nano-attapulgite, hexagonal boron nitride, and polyethylene particles are melted to obtain a modified polyethylene melt; wherein the melting temperature is 190-230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 2.5%, the mass fraction of the hexagonal boron nitride is 1.25%, and the balance is the polyethylene particles.

[0086] (2) pressurizing the spinning solvent to 8 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 10%, and the remainder is the spinning solvent;

[0087] (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot-rolling to obtain a flash spun sheet material.

[0088] The flash-spun sheet material in this comparative example can be used in the textile field or medical packaging.

[0089] Table 1 Test results of this application

[0090] Single stripping degree N·s / mm Peel strength in CD direction N Example 1 22.6 0.58 Example 2 58.9 0.98 Example 3 82.3 1.42 Comparative Example 1 5.9 0.33 Comparative Example 2 4.4 0.21 Comparative Example 3 4.9 0.25 Comparative Example 4 115.4 1.62

[0091] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the concept of the present invention. These improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A flash-spun sheet material with a better single peeling degree, characterized in that: The raw material of the flash-spun sheet material comprises polyethylene, and the thickness of the flash-spun sheet material is 0.11 to 0.29 mm; The single peeling degree of flash-spun sheet material is 10 to 110 (N·s / mm); Single peel strength = (logarithmic peel strength * Gurley air resistance) / thickness; The peeling strength of the flash-spun sheet material in the CD direction is greater than that in the MD direction; The test standard for peel strength is the peel strength test method for adhesive interlining garments FZ / T 80007.1-2006; The test standard for Gurley air resistance is GB / T 458-2008, which states that paper and board—Determination of air permeability. Gurley air resistance is measured by measuring the time it takes for 100 ml of gas to pass through.

2. A flash-spun sheet material with a better single peeling degree as claimed in claim 1, characterized in that: The CD direction peeling strength of the flash spun sheet material is greater than 0.4N.

3. The flash-spun sheet material with a better single peeling degree according to claim 1, characterized in that: The CD direction peeling strength of the flash spun sheet material is greater than 0.5N.

4. The flash-spun sheet material with a better single peeling degree according to claim 1, characterized in that: The CD direction peeling strength of the flash spun sheet material is greater than 0.6N.

5. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The CD direction peeling strength of the flash spun sheet material is greater than 0.7N.

6. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling degree of the flash-spun sheet material is 10 to 20 (N·s / mm).

7. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling degree of the flash-spun sheet material is 20 to 30 (N·s / mm).

8. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling strength of the flash-spun sheet material is 30 to 40 (N·s / mm).

9. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling degree of the flash-spun sheet material is 50 to 60 (N·s / mm).

10. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling strength of the flash-spun sheet material is 60 to 70 (N·s / mm).

11. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling strength of the flash-spun sheet material is 70 to 80 (N·s / mm).

12. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling strength of the flash-spun sheet material is 80 to 90 (N·s / mm).

13. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The single peeling strength of the flash-spun sheet material is 90 to 100 (N·s / mm).

14. The flash-spun sheet material with better single peeling degree according to claim 1, characterized in that: The thickness of the flash-spun sheet material is 0.15 to 0.20 mm.

15. Use of the flash-spun sheet material with better single peeling degree as claimed in claim 1 in the textile field or medical packaging.

16. The method for processing a flash-spun sheet material with a better single peeling degree according to claim 1, wherein: The technical steps involved are: (1) melting nano-attapulgite, hexagonal boron nitride, and polyethylene particles to obtain a modified polyethylene melt; wherein the melting temperature is 190 to 230° C.; in the modified polyethylene melt, the mass fraction of the nano-attapulgite is 1 to 2%, the mass fraction of the hexagonal boron nitride is 0.5 to 1%, and the balance is the polyethylene particles; (2) pressurizing the spinning solvent to 6-9 MPa, then heating it to 190-230° C., and introducing it into a mixer through a pipeline with the modified polyethylene melt obtained in step (1), where they are stirred and mixed to obtain a flash spinning solution; wherein the mass fraction of the modified polyethylene melt in the flash spinning solution is 7-16%, and the remainder is the spinning solvent; (3) flash spinning the flash spinning solution obtained in step (2) at a flash spinning temperature of 200-230° C. to obtain flash spun fibers, laying the flash spun fibers into a web, and then hot rolling them to obtain a flash spun sheet material.

Images